Development of high-Tc iron-based superconductors using co-doping and study on the mechanism of the increase in Tc induced by this method

• Project/Area Number: 25400372
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Condensed matter physics II
• Research Institution: Okayama University
• Principal Investigator: Kudo Kazutaka 岡山大学, 自然科学研究科, 准教授 (40361175)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥4,940,000 (Direct Cost: ¥3,800,000、Indirect Cost: ¥1,140,000); Fiscal Year 2015: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000); Fiscal Year 2014: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2013: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: 高温超伝導 / 鉄系超伝導体 / コドープ / 新物質開発

Outline of Final Research Achievements

In iron-based arsenides, systematic studies on chemical doping have led to the highest superconducting transition temperature Tc of 55 K in SmFeAsO1-xFx among 1111-type compounds and 38 K in Ba1-xKxFe2As2 among 122-type compounds. It seems that there is no room left for enhancement of Tc in terms of chemical doping. Here, in this research project, we studied the mechanism of the increase in Tc up to 45 K in La and P co-doped 122-type CaFe2As2. Our result revealed that the superconducting phase is far from the antiferromagnetic phase in the co-doped CaFe2As2, and also suggested that the fluctuation between forming and breaking As2 dimers could be responsible for the emergence of superconductivity. Moreover, we found that co-doping also enhances Tc in the 112-type Ca1-xRExFeAs2. The additional doping of Sb increases the Tc of Ca1-xLaxFeAs2 from 35 to 47 K. These results suggested that the co-doping sheds light on a novel route to develop iron-based superconductors with higher Tc.

Research Products

• [Int'l Joint Research] Chinese Academy of Sciences(China)
• [Int'l Joint Research] IVIC/Universidad Central de Venezuela(Venezuela)
• [Journal Article] A new way to synthesize superconducting metal-intercalated C60 and FeSe (2016)
  • Author(s): Y. Takahei, K. Tomita, Y. Itoh, K. Ashida, J.-H. Lee, N. Nishimoto, T. Kimura, K. Kudo, Minoru Nohara, Y. Kubozono, T. Kambe
  • Journal Title: Scientific Reports Volume: 6 Issue: 1 Pages: 18931-18931
  • DOI: 10.1038/srep18931
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] High-resolution magnetic penetration depth and inhomogeneities in locally noncentrosymmetric SrPtAs (2016)
  • Author(s): J. F. Landaeta, S. V. Taylor, I. Bonalde, C. Rojas, Y. Nishikubo, K. Kudo, M. Nohara
  • Journal Title: Physical Review B Volume: 93 Issue: 6
  • DOI: 10.1103/physrevb.93.064504
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Observation of momentumresolved charge fluctuations proximate to the charge-order phase using resonant inelastic x-ray scattering (2016)
  • Author(s): M. Yoshida, K. Ishii, M. Naka, S. Ishihara, I. Jarrige, K. Ikeuchi, Y. Murakami, K. Kudo, Y. Koike, T. Nagata, Y. Fukada, N. Ikeda & J. Mizuki
  • Journal Title: Scientific Reports Volume: 6 Issue: 1 Pages: 23611-23611
  • DOI: 10.1038/srep23611
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Enhancement of critical current density in a Ca0.85La0.15Fe(As0.92Sb0.08)2 superconductor with Tc = 47 K through 3 MeV proton irradiation (2016)
  • Author(s): A. Park, A. Mine, T. Yamada, F. Ohtake, H. Akiyama, Y. Sun, S. Pyon, T. Tamegai, Y. Kitahama, T. Mizukami, K. Kudo, M. Nohara, H. Kitamura
  • Journal Title: Superconductor Science and Technology Volume: 29 Issue: 5 Pages: 055006-055006
  • DOI: 10.1088/0953-2048/29/5/055006
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Comparative ARPES Study on Iron-Platinum-Arsenide Superconductor Ca10(Pt4As8)(Fe2－xPtxAs2)5 (x = 0.25 and 0.42) (2015)
  • Author(s): M. Sunagawa, R. Yoshida, T. Ishiga, K. Tsubota, T. Jabuchi, J. Sonoyama, S. Kakiya, D. Mitsuoka, K. Kudo, M. Nohara, K. Ono, H. Kumigashira, T. Oguchi, T. Wakita, Y. Muraoka, T. Yokoya
  • Journal Title: Journal of the Physical Society of Japan Volume: 84 Issue: 5 Pages: 055001-055002
  • DOI: 10.7566/jpsj.84.055001
  • NAID: 210000133564
  • Peer Reviewed
• [Journal Article] Superconductivity in MgPtSi: An orthorhombic variant of MgB2 (2015)
  • Author(s): Kazutaka Kudo, Kazunori Fujimura, Seiichiro Onari, Hiromi Ota, Minoru Nohara
  • Journal Title: Physical Review B Volume: 91 Issue: 17
  • DOI: 10.1103/physrevb.91.174514
  • Peer Reviewed
• [Journal Article] Suppression of Nonmagnetic Insulating State by Application of Pressure in Mineral Tetrahedrite Cu12Sb4S13 (2015)
  • Author(s): S. Kitagawa, T. Sekiya, S. Araki, T. C. Kobayashi, K. Ishida, T. Kambe, T. Kimura, N. Nishimoto, K. Kudo, M. Nohara
  • Journal Title: Journal of the Physical Society of Japan Volume: 84 Issue: 9 Pages: 0939011-4
  • DOI: 10.7566/jpsj.84.093701
  • NAID: 210000133657
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Development of High-Pressure and Multi-Frequency ESR System and Its Application to Quantum Spin System (2015)
  • Author(s): T. Sakurai, R. Matsui, K. Kawasaki, S. Okubo, H. Ohta, K. Matsubayashi, Y. Uwatoko, K. Kudo, Y. Koike
  • Journal Title: Applied Magnetic Resonance Volume: 46 Issue: 9 Pages: 1007-1012
  • DOI: 10.1007/s00723-015-0660-9
  • Peer Reviewed
• [Journal Article] Frequency Extension to the THz Range in the High Pressure ESR System and Its Application to the Shastry－Sutherland Model Compound SrCu2(BO3)2 (2015)
  • Author(s): H. Ohta, T. Sakurai, R. Matsui, K. Kawasaki, Y. Hirao, S. Okubo, K. Matsubayashi, Y. Uwatoko, K. Kudo, Y. Koike
  • Journal Title: The Journal of Physical Chemistry B Volume: 119 Issue: 43 Pages: 13755-13761
  • DOI: 10.1021/acs.jpcb.5b03664
  • Peer Reviewed
• [Journal Article] Doping-enhanced antiferromagnetism in Ca1-xLaxFeAs2 (2015)
  • Author(s): S. Kawasaki, T. Mabuchi, S. Maeda, T. Adachi, T. Mizukami, K. Kudo, M. Nohara, G.-q. Zheng
  • Journal Title: Physical Review B Volume: 92 Issue: 18
  • DOI: 10.1103/physrevb.92.180508
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Unscalling Superconducting Parameters with Tc for Bi-2212 and Bi-2223: A Magnetotransport Study in the Superconductive Fluctuation Regime (2015)
  • Author(s): S. Adachi, T. Usui, Y. Ito, H. Kudo, H. Kushibiki, K. Murata, T. Watanabe, K. Kudo, T. Nishizaki, N. Kobayashi, S. Kimura, M. Fujita, K. Yamada, T. Noji, Y. Koike, T. Fujii,
  • Journal Title: J. Phys. Soc. Jpn. Volume: 84 Issue: 2 Pages: 0247061-0247066
  • DOI: 10.7566/jpsj.84.024706
  • NAID: 210000133435
  • Peer Reviewed / Open Access
• [Journal Article] Real Space Imaging of Spin Polarons in Zn-Doped SrCu2(BO3)2 (2015)
  • Author(s): M. Yoshida, H. Kobayashi, I. Yamauchi, M. Takigawa, S. Capponi, D. Poilblanc, F. Mila, K. Kudo, Y. Koike, and N. Kobayashi
  • Journal Title: Phys. Rev. Lett. Volume: 114 Issue: 5
  • DOI: 10.1103/physrevlett.114.056402
  • Peer Reviewed
• [Journal Article] Coexistence of multiple charge-density waves and superconductivity in SrPt2As2 revealed by 75As-NMR/NQR and 195Pt-NMR (2015)
  • Author(s): S. Kawasaki, Y. Tani, T. Mabuchi, K. Kudo, Y. Nishikubo, D. Mitsuoka, M. Nohara, and G.-q. Zheng
  • Journal Title: Phys. Rev. B Volume: 91 Issue: 6
  • DOI: 10.1103/physrevb.91.060510
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Spin-singlet superconductivity with a full gap in locally noncentrosymmetric SrPtAs (2014)
  • Author(s): K. Matano, K. Arima, S. Maeda, Y. Nishikubo, K. Kudo, M. Nohara, Guo-qing Zheng
  • Journal Title: Physical Review B Volume: 89 Issue: 14
  • DOI: 10.1103/physrevb.89.140504
  • Peer Reviewed
• [Journal Article] Thermal Conductivity due to Spinons in the One-Dimensional Quantum Spin System Sr2V3O9 (2014)
  • Author(s): T. Kawamata, M. Uesaka, M. Sato, K. Naruse, K. Kudo, N. Kobayashi, and Y. Koike
  • Journal Title: Journal of the Physical Society of Japan Volume: 83 Issue: 5 Pages: 054601-054601
  • DOI: 10.7566/jpsj.83.054601
  • NAID: 210000133077
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Pudding-Mold-Type Band as an Origin of the Large Seebeck Coefficient Coexisting with Metallic Conductivity in Carrier-Doped FeAs2 and PtSe2 (2014)
  • Author(s): H. Usui, K. Kuroki, S. Nakano, K. Kudo, and M. Nohara
  • Journal Title: Journal of Electronic Materials Volume: 43 Issue: 6 Pages: 1656-1661
  • DOI: 10.1007/s11664-013-2823-5
  • Peer Reviewed
• [Journal Article] Doping Dependencies of Onset Temperatures for the Pseudogap and Superconductive Fluctuation in Bi2Sr2CaCu2O8+d, Studied from Both In-Plane and Out-of-Plane Magnetoresistance Measurements (2014)
  • Author(s): T. Usui, D. Fujiwara, S. Adachi, H. Kudo, K. Murata, H. Kushibiki, T. Watanabe, K. Kudo, T. Nishizaki, N. Kobayashi, S. Kimura, K. Yamada, T. Naito, T. Noji, and Y. Koike
  • Journal Title: Journal of the Physical Society of Japan Volume: 83 Issue: 6 Pages: 064713-064713
  • DOI: 10.7566/jpsj.83.064713
  • Peer Reviewed
• [Journal Article] Angle-Resolved Photoemission Study on Multi-Band Electronic Structure of IrTe2 (2014)
  • Author(s): D. Ootsuki, S. Pyon, K. Kudo, M. Nohara, M. Horio, T. Yoshida, A. Fujimori, M. Arita, H. Anzai, H. Namatame, M. Taniguchi, N. L. Saini, and T. Mizokawa
  • Journal Title: JPS Conference Proceedings Volume: 3
  • DOI: 10.7566/jpscp.3.016015
  • Peer Reviewed / Open Access
• [Journal Article] Coexistence of Bloch Electrons and Glassy Electrons in Ca10(Ir4As8)(Fe2-xIrxAs2)5revealedby angle-resolved Photoemission Spectroscopy (2014)
  • Author(s): K. Sawada, D. Ootsuki,K. Kudo, D. Mitsuoka, M. Nohara, T. Noda, K. Horiba, M. Kobayashi, K. Ono, H. Kumigashira, N. L. Saini, T. Mizokawa
  • Journal Title: Physical Review B Volume: 89 Issue: 22 Pages: 220508-220508
  • DOI: 10.1103/physrevb.89.220508
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Bond-Order and the Role of Ligand States in Stripe-Modulated IrTe2 (2014)
  • Author(s): K. Takubo, R. Comin, D. Ootsuki,T. Mizokawa, H. Wadati, Y. Takahashi, G. Shibata, A. Fujimori, R. Sutarto, F. He, S. Pyon, K. Kudo, M. Nohara, G. Levy, I. Elfmov, G. A. Sawatzky, A. Damascelli
  • Journal Title: Physical Review B Volume: 90 Issue: 8 Pages: 081104-081104
  • DOI: 10.1103/physrevb.90.081104
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Superconducting Transition Temperatures of up to 47 K from Simultaneous Rare-Earth Element and Antimony Doping of 112-Type CaFeAs2 (2014)
  • Author(s): K. Kudo, Y. Kitahama, K. Fujimura, T. Mizukami, H. Ota, and M. Nohara
  • Journal Title: Journal of the Physical Society of Japan Volume: 83 Issue: 9 Pages: 093705-093705
  • DOI: 10.7566/jpsj.83.093705
  • NAID: 210000133243
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Superconductivity in Noncentrosymmetric Iridium Silicide Li2IrSi3 (2014)
  • Author(s): S. Pyon, K. Kudo, J. Matsumura, H. Ishii, G. Matsuo, M. Nohara, H. Hojo, K. Oka, M. Azuma, V. Ovidiu Garlea, K. Kodama, and S. Shamoto
  • Journal Title: Journal of the Physical Society of Japan Volume: 83 Issue: 9 Pages: 093706-093706
  • DOI: 10.7566/jpsj.83.093706
  • NAID: 210000133244
  • Peer Reviewed
• [Journal Article] Temperature dependent nanoscale atomic correlations in Ir1-xPtxTe2 (x = 0.0, 0.03 and 0.04) system (2014)
  • Author(s): B. Joseph, E. Paris, D. F. Mulato-Gomez, L. Simonelli, M. Bendele, L. Maugeri, A. Iadecola, S. Pyon, K. Kudo, M. Nohara, J. Mustre de Leon, T. Mizokawa, and N. L. Saini
  • Journal Title: Journal of Physics: Condensed Matter Volume: 26 Issue: 37 Pages: 375702-375702
  • DOI: 10.1088/0953-8984/26/37/375702
  • Peer Reviewed
• [Journal Article] Determination of temperature-dependent atomic displacements in the Ca10Ir4As8(Fe2As2)5 (2014)
  • Author(s): E. Paris, B. Joseph, A. Iadecola, C. Marini, K. Kudo, D. Mitsuoka, M. Nohara, T. Mizokawa, and N. L. Saini
  • Journal Title: Physical Review B Volume: 90 Issue: 9 Pages: 094508-094508
  • DOI: 10.1103/physrevb.90.094508
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Synchrotron X-ray diffraction study of the Structural Phase Transition in Ca10(Ir4As8)(Fe2-xIrxAs2)5 (2014)
  • Author(s): N. Katayama, K. Sugawara, Y. Sugiyama, T. Higuchi, K. Kudo, D. Mitsuoka, T. Mizokawa, M. Nohara, and Hiroshi Sawa
  • Journal Title: J. Phys. Soc. Jpn. Volume: 83 Issue: 11 Pages: 1-5
  • DOI: 10.7566/jpsj.83.113707
  • NAID: 210000133325
  • Peer Reviewed
• [Journal Article] Effectof Pt Substitution on the Electronic Structure of AuTe2 (2014)
  • Author(s): D. Ootsuki,K. Takubo,K. Kudo,H. Ishii, M. Nohara,N. L. Saini, R. Autarto, F. He, T. Z. Regier, G. Levy, G. A. Sawatzky, A. Damascelli, T. Mizokawa
  • Journal Title: Physical Review B Volume: 90 Issue: 14 Pages: 144515-144515
  • DOI: 10.1103/physrevb.90.144515
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Simultaneous suppression of superconductivity and structural phase transition under pressure in Ca10(Ir4As8)(Fe2-xIrxAs2)5 (2014)
  • Author(s): S. Kitagawa, S. Araki, T. C. Kobayashi, H. Ishii, K. Fujimura, D. Mitsuoka, K. Kudo, and M. Nohara
  • Journal Title: Physical Review B Volume: 90 Issue: 22
  • DOI: 10.1103/physrevb.90.224513
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Momentum-resolved resonant inelastic x-ray scattering on a single crystal under high pressure (2014)
  • Author(s): Masahiro Yoshida, Kenji Ishii, Ignace Jarrige, Tetsu Watanuki, Kazutaka Kudo, Yoji Koike, Ken'ichi Kumagai, Nozomu Hiraoka, Hirofumi Ishii, Ku-Ding Tsuei, and Jun'ichiro Mizuki
  • Journal Title: Journal of Synchrotron Radiation Volume: 21 Issue: 1 Pages: 131-135
  • DOI: 10.1107/s1600577513028944
  • Peer Reviewed
• [Journal Article] Charge-orbital-lattice coupling effects in the dd excitation profile of one-dimensional cuprates (2014)
  • Author(s): J. J. Lee, B. Moritz, W. S. Lee, M. Yi, C. J. Jia, A. P. Sorini, K. Kudo, Y. Koike, K. J. Zhou, C. Monney, V. Strocov, L. Patthey, T. Schmitt, T. P. Devereaux, and Z. X. Shen
  • Journal Title: Physical Review B Volume: 89 Issue: 4
  • DOI: 10.1103/physrevb.89.041104
  • Peer Reviewed
• [Journal Article] Enhanced Superconductivity up to 43 K by P/Sb Doping of Ca1－xLaxFeAs2 (2014)
  • Author(s): K. Kudo, T. Mizukami, Y. Kitahama, D. Mitsuoka, K. Iba, K. Fujimura, N. Nishimoto, Y. Hiraoka, M. Nohara
  • Journal Title: Journal of Physical the Society of Japan Volume: 83 Issue: 2 Pages: 025001-025001
  • DOI: 10.7566/jpsj.83.025001
  • NAID: 210000132976
  • Peer Reviewed
• [Journal Article] Switching of Conducting Planes by Partial Dimer Forrnation in lrTe_2 (2014)
  • Author(s): T. Toriyama M. Kobori, T. Konishi, Y. Ohta, K. Sugimoto, J. Kim, A. Fujiwara, S. Pyon, K. Kudo, M. Nohara
  • Journal Title: Journal ofthe Physical Society of Japan Volume: 83 Issue: 3 Pages: 33701-33701
  • DOI: 10.7566/jpsj.83.033701
  • Peer Reviewed
• [Journal Article] Important Roles of Te 5p and lr 5d Spin-Orbit lnteractions on the Multi-bandElectronic Structure ofTriangular Lattice Superconductor Ir_<1-x>Pt_xTe_2 (2014)
  • Author(s): D. Ootsuki, T. Toriyama M. Kobayashi, S. Pyon, K. Kudo, M. Nohara T. Sugimoto, T. Yoshida, M. Horio, A. Fujimori, M. Arita, H. Anzai, H, Namatame, M. Taniguchi, N. L. saini, T. Konishi, Y. Ohta, and T. Mizokawa
  • Journal Title: Journal of the Physical Society of Japan Volume: 83 Issue: 3 Pages: 33704-33704
  • DOI: 10.7566/jpsj.83.033704
  • Peer Reviewed
• [Journal Article] Te 5 p orbitals bring three-dimensional electronic structure to two-dimensional Ir_<0.95>Pt_<0.05>Te_2 (2014)
  • Author(s): D. Ootsuki. T. Toriyama, S. Pyon, K. Kudo, M. Nohara, K. Horiba, M. Kobayashi, K. Ono, H. Kumigashira, T. Noda, T. Sugimoto, A. Fujimori, N. LSaini, T. Konishi, Y. Ohta, T. Mizokawa
  • Journal Title: Physical Review B Volume: 89 Issue: 10
  • DOI: 10.1103/physrevb.89.104506
  • Peer Reviewed
• [Journal Article] Characteristic two-dimensional Fermi surface topology of high-Tc iron-based superconductors (2014)
  • Author(s): Sunagawa,M.Ishiga, T ，Tsubota, K，Jabuchi, T，Sonoyama, J，Iba, K，Kudo, K，Nohara, M，Ono, K，Kumigashira, H，Matsushita, T，Arita, M，Shimada, K ，Namatame, H，Taniguchi, M，Wakita, T，Muraoka, Y ，Yokoya, T，
  • Journal Title: SCIENTIFIC REPORTS Volume: 4 Issue: 1 Pages: 4381-4381
  • DOI: 10.1038/srep04381
  • Peer Reviewed
• [Journal Article] Band Jahn-Teller effects and Peierls Instability in IrTe_2 (2013)
  • Author(s): D. Ootsuki, S. Pyon, K. Kudo, M. Nohara, M. Horio, T. Yoshida, A. Fujimori, M. Arita, H. Anzai, H. Namatame, M. Taniguchi, N. L. Saini, T. Mizokawa
  • Journal Title: Journal of Physics : Conference Series Volume: Vol.428 Pages: 012018-012018
  • DOI: 10.1088/1742-6596/428/1/012018
  • Peer Reviewed
• [Journal Article] Superconductivity induced by breaking Te2 dimers of AuTe2 (2013)
  • Author(s): K. Kudo, H. Ishii, M. Takasuga, K. Iba, S. Nakano, J. Kim, A. Fujiwara, and M. Nohara
  • Journal Title: Journal of the Physical Society of Japan Volume: 82 Issue: 6 Pages: 063704-063704
  • DOI: 10.7566/jpsj.82.063704
  • Peer Reviewed
• [Journal Article] Collapsed Tetragonal Phase Transition of Ca(Fe1-xRhx)2As2 Studied by Photoemission Spectroscopy (2013)
  • Author(s): K. Tsubota, T. Wakita, H. Nagao, C. Hiramatsu, T. Ishiga, M. Sunagawa, K. Ono, H. Kumigashira, M. Danura, K. Kudo, M. Nohara, Y. Muraoka, T. Yokoya
  • Journal Title: Journal of the Physical Society of Japan Volume: 82 Issue: 7 Pages: 073705-073705
  • DOI: 10.7566/jpsj.82.073705
  • NAID: 210000132632
  • Peer Reviewed
• [Journal Article] Role of Lattice Coupling in Establishing Electronic and Magnetic Properties in Quasi-One-Dimensional Cuprates (2013)
  • Author(s): W. S. Lee, S. Johnston, B. Moritz, J. Lee, M. Yi, K. J. Zhou, T. Schmitt, L. Patthey, V. Strocov, K. Kudo, Y. Koike, J. van den Brink, T. P. Devereaux, and Z. X. Shen
  • Journal Title: Physical Review Letters Volume: 110 Issue: 26
  • DOI: 10.1103/physrevlett.110.265502
  • Peer Reviewed
• [Journal Article] Suppression of Structural Phase Transition in IrTe2 by Isovalent Rh Doping (2013)
  • Author(s): Kazutaka Kudo, Masakazu Kobayashi, Sunseng Pyon and Minoru Nohara
  • Journal Title: Journal of the Physical Society of Japan Volume: ８２ Issue: 8 Pages: 85001-85001
  • DOI: 10.7566/jpsj.82.085001
  • Peer Reviewed
• [Journal Article] Development of Hybrid Type Pressure Cell for High Pressure and High field ESR Measurement (2013)
  • Author(s): K. Fujimoto, T. Sakurai, S. Okubo, H. Ohta, K. Matsubayashi, Y. Uwatoko, K. Kudo, Y. Koike
  • Journal Title: Appl. Mag. Res Volume: 44 Issue: 8 Pages: 893-898
  • DOI: 10.1007/s00723-013-0441-2
  • Peer Reviewed
• [Journal Article] Electronic Structure Reconstruction by Orbital Symmetry Breaking in IrTe_2 (2013)
  • Author(s): D. Ootsuki, S. Pyon, K. Kudo, M. Nohara, M. Horio, T. Yoshida, A. Fujimori, M. Arita, H. Anzai, H. Namatame, M. Taniguchi, N. L. saini, T. Mizokawa
  • Journal Title: Journal of the Physical Society of Japan Volume: 82 Issue: 9 Pages: 93704-93704
  • DOI: 10.7566/jpsj.82.093704
  • Peer Reviewed
• [Journal Article] Large Seebeck effect in electron-doped FeAs2 driven by a quasi-one-dimensional pudding-mold-type band (2013)
  • Author(s): H. Usui, K. Suzuki, K. Kuroki, S. Nakano, K. Kudo, and M. Nohara
  • Journal Title: Physical Review B Volume: 88 Issue: 7
  • DOI: 10.1103/physrevb.88.075140
  • Peer Reviewed
• [Journal Article] Enhancing high-temperature thermoelectric properties of PtAs2 by Rh doping (2013)
  • Author(s): K. Kudo, S. Nakano, T. Mizukami, T. Takabatake, and M. Nohara
  • Journal Title: Applied Physics Letters Volume: 103 Issue: 9
  • DOI: 10.1063/1.4819953
  • Peer Reviewed
• [Journal Article] Emergence of superconductivity near the structural phase boundary in Pt-doped IrTe2 single crystals (2013)
  • Author(s): Sunseng Pyon, Kazutaka Kudo, and Minoru Nohara
  • Journal Title: Physica C Volume: 494 Pages: 80-84
  • DOI: 10.1016/j.physc.2013.04.055
  • Peer Reviewed
• [Journal Article] Pressure-Induced Superconductivity in Mineral Calaverite AuTe_2 (2013)
  • Author(s): S. Kitagawa, et al.
  • Journal Title: Journal of the Physical Society of Japan Volume: 82 Issue: 11 Pages: 113704-113704
  • DOI: 10.7566/jpsj.82.113704
  • Peer Reviewed
• [Journal Article] Superconductivity in Ca10(Ir4As8)(Fe2As2)5 with Square-Planar Coordination of Iridium (2013)
  • Author(s): K. Kudo, D. Mitsuoka, M. Takasuga, Y. Sugiyama, K. Sugawara, N. Katayama, H. Sawa, H. S. Kubo, K.
  • Journal Title: Scientific Reports Volume: 3 Issue: 1 Pages: 1-5
  • DOI: 10.1038/srep03101
  • Peer Reviewed
• [Journal Article] Superconductivity in Ca1-xLaxFeAs2: A Novel 112-Type Iron Pnictide with Arsenic Zigzag Bonds (2013)
  • Author(s): N. Katayama, K. Kudo, S. Onari, T. Mizukami, K. Sugawara, Y. Sugiyama, Y. Kitahama, K. Iba, K. Fujimura, N. Nishimoto, M. Nohara, and H. Sawa
  • Journal Title: J. Phys. Soc. Jpn, Volume: 82 Issue: 12 Pages: 1-10
  • DOI: 10.7566/jpsj.82.123702
  • NAID: 210000132852
  • Peer Reviewed / Open Access
• [Journal Article] Local structural displacements across the structural phase transition in IrTe_2 : Order-disorder of dimers and role of Ir-Te correlations (2013)
  • Author(s): B. Joseph, M. Bendele, L. Simonelli, L. Maugeri, S. Pyon, K. Kudo, M. Nohara, T. Mizokawa, and N. L. Saini
  • Journal Title: Physical Review B Volume: Vol.88 Issue: 22
  • DOI: 10.1103/physrevb.88.224109
  • Peer Reviewed
• [Presentation] PドープCrAsにおけるヘリカル磁性の抑制と量子臨界現象 (2016)
  • Author(s): 工藤一貴，松尾元太，西本直生，竹内貴亮，藤村一徳，野原実
  • Organizer: 日本物理学会第71回年次大会
  • Place of Presentation: 東北学院大学（宮城県・仙台市）
  • Year and Date: 2016-03-19
• [Presentation] Ir1-xPtxTe2の共鳴X線散乱 (2016)
  • Author(s): 田久保耕，和達大樹，大槻太毅，溝川貴司，R. Sutarto，F. He，石井賢司，卞舜生，工藤一貴，松尾元太，石井博文，小林正和，野原実
  • Organizer: 日本物理学会第71回年次大会
  • Place of Presentation: 東北学院大学（宮城県・仙台市）
  • Year and Date: 2016-03-19
• [Presentation] SrCu2(BO3)2のテラヘルツ領域における圧力下ESR測定II (2016)
  • Author(s): 平尾祐樹，櫻井敬博，太田仁，大久保晋，肘井敬吾，松林和幸，上床美也，工藤一貴，小池洋二
  • Organizer: 日本物理学会第71回年次大会
  • Place of Presentation: 東北学院大学（宮城県・仙台市）
  • Year and Date: 2016-03-19
• [Presentation] ヒ化物系層間物質をもつ鉄系超伝導体のSbドープによるTc上昇 (2016)
  • Author(s): 木村拓海，工藤一貴，北濱裕，水上輔，藤村一徳，井岡賢志，西本直生，太田弘道，野原実
  • Organizer: 日本物理学会第71回年次大会
  • Place of Presentation: 東北学院大学（宮城県・仙台市）
  • Year and Date: 2016-03-19
• [Presentation] 単結晶LiX(NH3)yFe2-dSe2の超伝導物性 (2016)
  • Author(s): 李智鉉，宮島瑞樹，角藤壮，伊藤雄吾，西本直生，木村拓海，工藤一貴，野原実，神戸高志
  • Organizer: 日本物理学会第71回年次大会
  • Place of Presentation: 東北学院大学（宮城県・仙台市）
  • Year and Date: 2016-03-19
• [Presentation] BaPtAsにおける多形制御と超伝導 (2016)
  • Author(s): 竹内貴亮，工藤一貴，藤村一徳，太田弘道，野原実
  • Organizer: 日本物理学会第71回年次大会
  • Place of Presentation: 東北学院大学（宮城県・仙台市）
  • Year and Date: 2016-03-19
• [Presentation] PrドープCaFe2As2の蛍光X線ホログラフィー:ドーパント周りの局所構造解析 (2016)
  • Author(s): 井岡賢志，工藤一貴，太田弘道，木村拓海，戎佳宏，波田拓馬，小関正哉，八方直久，林好一，野原実
  • Organizer: 日本物理学会第71回年次大会
  • Place of Presentation: 東北学院大学（宮城県・仙台市）
  • Year and Date: 2016-03-19
• [Presentation] PrドープCaFe2As2の超伝導とドーパント周りの局所構造 (2016)
  • Author(s): 工藤一貴
  • Organizer: 科研費新学術領域研究「3D活性サイト科学」第３回成果報告会
  • Place of Presentation: 名古屋工業大学（愛知県・名古屋市）
  • Year and Date: 2016-03-07
• [Presentation] 鉄系および関連物質における新規超伝導体の開発とドープ原子ホログラフィー (2015)
  • Author(s): 工藤一貴
  • Organizer: 「3D活性サイト科学」第４回サイトビジット
  • Place of Presentation: 岡山大学（岡山県・岡山市）
  • Year and Date: 2015-12-05
• [Presentation] 鉄系および関連物質における新規超伝導体の開発 (2015)
  • Author(s): 工藤一貴
  • Organizer: 2015年日本化学会中国四国支部大会，若手セッション「エキゾチックな超伝導体の新展開」
  • Place of Presentation: 岡山大学（岡山県・岡山市）
  • Year and Date: 2015-11-14
  • Invited
• [Presentation] BaNi2(As1-xPx)2の角度分解光電子分光 (2015)
  • Author(s): 野田智博，大槻太毅，杉本拓也，堀尾眞史，藤森淳，小林正起，堀場弘司，小野寛太，組頭広志，工藤一貴，高須賀政哉，野原実，N. L. Saini，溝川貴司
  • Organizer: 日本物理学会2015年秋季大会
  • Place of Presentation: 関西大学（大阪府・吹田市）
  • Year and Date: 2015-09-16
• [Presentation] Lix(NH3)yFe2-dSe2の複数の超伝導相とその物性 (2015)
  • Author(s): イジヒョン，角藤壮，伊藤雄吾，西本直生，木村拓海，工藤一貴，野原実，神戸高志
  • Organizer: 日本物理学会2015年秋季大会
  • Place of Presentation: 関西大学（大阪府・吹田市）
  • Year and Date: 2015-09-16
• [Presentation] レーザー角度分解光電子分光によるIr1-xPtxTe2の超伝導ギャップの直接観測 (2015)
  • Author(s): 大槻太毅，溝川貴司，N.L. Saini，大田由一，山本遇哲，橋本嵩広，岡崎浩三，辛埴，藤森淳，鳥山達矢，小西健久，太田幸則，卞舜生，工藤一貴，野原実
  • Organizer: 日本物理学会2015年秋季大会
  • Place of Presentation: 関西大学（大阪府・吹田市）
  • Year and Date: 2015-09-16
• [Presentation] 砒化物超伝導体SrPt2As2におけるCDWと超伝導のNMR/NQR法による研究 (2015)
  • Author(s): 川崎慎司，谷佳彦，馬渕知佑，工藤一貴，西窪義博，光岡大輔，野原実，鄭国慶
  • Organizer: 日本物理学会2015年秋季大会
  • Place of Presentation: 関西大学（大阪府・吹田市）
  • Year and Date: 2015-09-16
• [Presentation] SrCu2(BO3)2のテラヘルツ領域における圧力下ESR測定 (2015)
  • Author(s): 平尾祐樹，櫻井敬博，太田仁，大久保晋，原茂生，松岡英一，菅原仁，松林和幸，上床美也，工藤一貴，小池洋二
  • Organizer: 日本物理学会2015年秋季大会
  • Place of Presentation: 関西大学（大阪府・吹田市）
  • Year and Date: 2015-09-16
• [Presentation] 鉄系超伝導体Ca1-xLaxFeAs2の圧力-Laドープ量-温度3次元相図 (2015)
  • Author(s): 関谷泰志，北川俊作，荒木新吾，小林達生，西本直生，井岡賢志，藤村一徳，水上輔，工藤一貴，野原実
  • Organizer: 日本物理学会2015年秋季大会
  • Place of Presentation: 関西大学（大阪府・吹田市）
  • Year and Date: 2015-09-16
• [Presentation] 空間反転対称性の破れたハニカム格子超伝導体BaPt(As1-xSbx) (2015)
  • Author(s): 竹内貴亮，工藤一貴，藤村一徳，水上輔，太田弘道，野原実
  • Organizer: 日本物理学会2015年秋季大会
  • Place of Presentation: 関西大学（大阪府・吹田市）
  • Year and Date: 2015-09-16
• [Presentation] ThCr2Si2型BaPd2As2の超伝導 (2015)
  • Author(s): 山田芳明，工藤一貴，松尾元太，北濱裕，野原実
  • Organizer: 日本物理学会2015年秋季大会
  • Place of Presentation: 関西大学（大阪府・吹田市）
  • Year and Date: 2015-09-16
• [Presentation] AuドープPdTe2における電子状態密度の発散的増大による強結合超伝導 (2015)
  • Author(s): 工藤一貴，石井博文，野原実
  • Organizer: 科研費新学術領域研究「J-Physics : 多極子伝導系の物理」キックオフミーティング
  • Place of Presentation: 神戸大学統合研究拠点コンベンションホール（兵庫県・神戸市）
  • Year and Date: 2015-09-14
• [Presentation] AlB2派生構造を持つMgPtSiの超伝導 (2015)
  • Author(s): 藤村一徳，工藤一貴，野原実
  • Organizer: 科研費新学術領域研究「J-Physics : 多極子伝導系の物理」キックオフミーティング
  • Place of Presentation: 神戸大学統合研究拠点コンベンションホール（兵庫県・神戸市）
  • Year and Date: 2015-09-14
• [Presentation] 希土類ドープCaFe2As2の超伝導とドーパント周りの局所構造 (2015)
  • Author(s): 工藤一貴
  • Organizer: 科研費新学術領域研究「3D活性サイト科学」第２回成果報告会
  • Place of Presentation: KEKつくばキャンパス，筑波山京成ホテル（茨城県・つくば市）
  • Year and Date: 2015-09-04
• [Presentation] Drastic enhancement of superconducting transition temperature in 112-type Ca1-xRExFeAs2 (RE = La, Ce, Pr, Nd) induced by negative chemical pressure (2015)
  • Author(s): K. Kudo, Y. Kitahama, K. Fujimura, T. Mizukami, M. Nohara
  • Organizer: 20th International Conference on Magnetism
  • Place of Presentation: Barcelona (Spain)
  • Year and Date: 2015-07-05
  • Int'l Joint Research
• [Presentation] Precise phase control and superconductivity in Ax(NH3)yFe2-dSe2 system (A: Alkali and Alkali-earth metal) (2015)
  • Author(s): T. Kambe, K. Ashida, J.-H. Lee, Y. Takahei, N. Nishimoto, T. Kimura, K. Kudo, M. Nohara
  • Organizer: 20th International Conference on Magnetism
  • Place of Presentation: Barcelona (Spain)
  • Year and Date: 2015-07-05
  • Int'l Joint Research
• [Presentation] 鉄系超伝導体112型Ca1-xRExFeAs2における元素添加による超伝導転移温度の著しい上昇 (2015)
  • Author(s): 井岡賢志，北濱裕，水上輔，藤村一徳，工藤一貴，野原実
  • Organizer: 新学術領域「3D活性サイト科学」春の学校
  • Place of Presentation: 奈良春日野国際フォーラム（奈良県・奈良市）
  • Year and Date: 2015-05-30
• [Presentation] ドープ原子ホログラフィーによる高臨界温度鉄系超伝導体の設計と創成 (2015)
  • Author(s): 工藤一貴
  • Organizer: 科研費新学術領域研究「3D活性サイト科学」公募研究キックオフミーティング
  • Place of Presentation: SPring-8（兵庫県・佐用郡佐用町）
  • Year and Date: 2015-05-11
• [Presentation] 112型Ca1-xRExFeAs2の超伝導と化学置換効果 (2015)
  • Author(s): 工藤一貴，水上輔，北濱裕，藤村一徳，野原実
  • Organizer: 日本物理学会第70回年次大会
  • Place of Presentation: 早稲田大学（東京）
  • Year and Date: 2015-03-21 – 2015-03-24
• [Presentation] Superconductivity induced by dimer breaking of calaverite AuTe2 (2014)
  • Author(s): K. Kudo, H. Ishii, and M. Nohara
  • Organizer: Ushimado International Workshop on Physics and Chemistry of Novel Superconductors and Related Materials
  • Place of Presentation: Okayama, Japan
  • Year and Date: 2014-11-08 – 2014-11-10
• [Presentation] Superconductivity at 47 K in 112-type CaFeAs2 with simultaneous rare-earth element and antimony doping (2014)
  • Author(s): K. Kudo, Y. Kitahama, K. Fujimura, T. Mizukami, H. Ota, and M. Nohara
  • Organizer: Ushimado International Workshop on Physics and Chemistry of Novel Superconductors and Related Materials
  • Place of Presentation: Okayama, Japan
  • Year and Date: 2014-11-08 – 2014-11-10
• [Presentation] Superconductivity in Ca10(Ir4As8)(Fe2As2)5 with a metallic spacer layer (2014)
  • Author(s): K. Kudo, D. Mitsuoka, and M. Nohara
  • Organizer: Ushimado International Workshop on Physics and Chemistry of Novel Superconductors and Related Materials
  • Place of Presentation: Okayama, Japan
  • Year and Date: 2014-11-08 – 2014-11-10
• [Presentation] Sbドープ112型Ca1-xRExFeAs2の超伝導-負の化学圧力印加によるTc = 47 Kのバルク超伝導発現 (2014)
  • Author(s): 工藤一貴，北濱裕，藤村一徳，水上輔，太田弘道，野原実
  • Organizer: 京都大学基礎物理学研究所研究会「多自由度電子状態と電子相関が生み出す新奇超伝導の物理」
  • Place of Presentation: 京都大学（京都）
  • Year and Date: 2014-10-21 – 2014-10-22
• [Presentation] Transition from interfacial to bulk superconductivity in rare-earth doped CaFe2As2 (2014)
  • Author(s): K. Kudo, K. Iba, and M. Nohara
  • Organizer: The International Conference on Strongly Correlated Electron Systems (SCES2014)
  • Place of Presentation: Grenoble, France
  • Year and Date: 2014-07-07 – 2014-07-11
• [Presentation] Square-Planar Coordination of Iridium (II): Metallic Spacer Layers of Superconducting Ca10(Ir4As8)(Fe2As2)2 (2014)
  • Author(s): K. Kudo, D. Mitsuoka, and M. Nohara
  • Organizer: 2014 MRS Spring Meeting
  • Place of Presentation: San Francisco, USA
  • Year and Date: 2014-04-21 – 2014-04-25
• [Presentation] 鉄系および関連物質における新超伝導体の開発 (2014)
  • Author(s): 工藤一貴
  • Organizer: 日本物理学会第69回年次大会（第8回（2014年）日本物理学会若手奨励賞（領域8）受賞記念講演）
  • Place of Presentation: 東海大学（平塚）
• [Presentation] 平面四配位Ir4As8層を持つ鉄系超伝導体Ca10(Ir4As8)(Fe2As2)5の発見 (2014)
  • Author(s): 工藤一貴，光岡大輔，高須賀政哉，杉山由季，菅原健人，片山尚幸，澤博，久保宏昭，高森健太，市岡優典，藤井達生，溝川貴司，野原実
  • Organizer: 日本物理学会第69回年次大会
  • Place of Presentation: 東海大学（平塚）
• [Presentation] 分子状ダイマーの形成・切断による超伝導体開発 (2013)
  • Author(s): 工藤一貴
  • Organizer: 応用物理学会超伝導分科会第４７回研究会「高温超伝導体の鉱脈を探せ！」
  • Place of Presentation: 公益財団法人 国際超電導産業技術研究センター（ISTEC）（東京）
  • Invited
• [Presentation] Emergence of superconductivity at 45 K induced by La and P co-doping of CaFe2As2 (2013)
  • Author(s): K. Kudo
  • Organizer: ICC-IMR International Workshop “Superconductivity research advanced by new materials and spectroscopies”
  • Place of Presentation: Sendai, Japan
  • Invited
• [Presentation] Superconductivity at 45 K induced by La and P co-doping of CaFe2As2 (2013)
  • Author(s): K. Kudo, K. Iba, M. Takasuga, Y. Kitahama, J. Matsumura, M. Danura, Y. Nogami, and M. Nohara
  • Organizer: The International Conference on Strongly Correlated Electron Systems (SCES2013)
  • Place of Presentation: Tokyo, Japan
• [Presentation] LaとPをコドープしたCaFe2As¬2における臨界温度45 Kの超伝導 (2013)
  • Author(s): 工藤一貴
  • Organizer: 京都大学基礎物理学研究所研究会「鉄系高温超伝導の物理～スピンと軌道の協奏～」
  • Place of Presentation: 京都大学（京都）
  • Invited
• [Presentation] Emergence of superconductivity at 45 K by La and P co-doping of CaFe2As2 (2013)
  • Author(s): K. Kudo, K. Iba, and M. Nohara
  • Organizer: 26th International Symposium on Superconductivity (ISS2013)
  • Place of Presentation: Tokyo, Japan
  • Invited
• [Presentation] Superconductivity at 45 K in La and P co-doped CaFe2As2 (2013)
  • Author(s): K. Kudo, K. Iba, and M. Nohara
  • Organizer: International Workshop on Novel Superconductors and Super Materials 2013 (NS22013)
  • Place of Presentation: Tokyo, Japan
• [Presentation] 鉄系超伝導体の新物質開発 (2013)
  • Author(s): 工藤一貴
  • Organizer: CROSSroads of Users and J-PARC 第９回「超伝導、磁性とフラストレーション」
  • Place of Presentation: KEK（東海）
  • Invited
• [Remarks] 自然科学研究科（理）の野原教授と工藤准教授が論文賞 日本物理学会
  • URL: http://www.okayama-u.ac.jp/tp/news/news_id5680.html
• [Remarks] カナダのリサーチ会社 Advances in Engineering 社が注目
  • URL: http://www.okayama-u.ac.jp/tp/news/news_id3444.html
• [Remarks] 「次代を拓く-工業材料キーワード３２」に選出
  • URL: http://www.okayama-u.ac.jp/tp/news/news_id3106.html
• [Remarks] レアアースの含有量を減らした新しい高温超電導体を開発
  • URL: http://www.okayama-u.ac.jp/tp/release/release_id110.html
• [Remarks] 熱を電気に変換できる熱電物質の高性能化に成功
  • URL: http://www.okayama-u.ac.jp/up_load_files/soumu-pdf/press25/press-130925-10.pdf
• [Patent(Industrial Property Rights)] 鉄系超電導物質及びその製造方法 (2013)
  • Inventor(s): 澤博，片山尚幸，細野秀雄，野原実，工藤一貴
  • Industrial Property Rights Holder: 国立大学法人 岡山大学、名古屋大学、東京工業大学
  • Industrial Property Rights Type: 特許
  • Industrial Property Number: 2013-199997
  • Filing Date: 2013-09-26